Henricus Martellus's map, the Latinised name used by Heinrich Hammer. Florence (1489). In colour on paper, 300 x 470 mm. Fol. 68 verso and 69 recto of Add. Ms. 15760. British Library, London

The South American river system, from the Orinoco River in Venezuela to the Grande River in Tierra del Fuego (Argentina), on Martellus's map (1489) and a modern-day map. Courtesy of Paul Gallez and his work La Cola del Dragón:América del Sur en los mapas antiguos, medievales y renacentistas.

Distortion grid of South America on the London copy of Henricus Martellus's map. Based on that of Paul Gallez shown in La Cola del Dragón. The distortion grid enables the identification of Cabo San Roque, Cabo Frio, the Valdés Peninsula, Cabo Tres Puntas and Cabo San Francisco de Paula. As for mountains, Paul Gallez identifies three ranges in Colombia, the Guiana Highlands, the Brazilian Plateau, the Serra do Mar and also Lake Titicaca.

Andreas Walsperger's world map, Konstanz (l448). South is at the top and east is on the left. The great peninsula on the left is South America. The  castle with seven turrets represents the Earthly Paradise, situated near the mouth of the Orinoco River. Vatican Library, Ms. Palat. Lat. 1362. According to Roberto Almagiá's reproduction.

Trans-Ganges India and the Dragon's Tail (South America) in al-Khwarizmi's planisphere of 833. According to Hubert Daunicht's reconstruction.

Claudius Ptolemy (Ca 90-168 AD). Map of the world, Florence 1474. Coloured manuscript on parchment. Kept in the Vatican Library, Vatican City.

Yü Chi Fu's map, also known as the Map of the routes of Yü the Great. Engraved in stone in 1137 AD, though its existence was known of for some considerable time previously. The coastline is clearly marked and the precision of the river system is astonishing. It measures 0.9m x 0.9m. Anonymous draftsman. From the third volume of Joseph Needham's work Science and Civilisation in China, Cambridge University Press, 1959.

Alejandro Zorzi's sketch based on information given by Christopher and Bartolomé Columbus. Ca. 1503-1506/1516-1522. Sheet of paper measuring 100 x 165 mm. Biblioteca Nazionale Centrale, Florence.

Elephant trunks in Central America. In the ruins of the Mayan city of Copán (Honduras). Courtesy of Jaime Errázuriz, in Cuenca del Pacífico: 4.000 años de contactos culturales.

The wheel was indeed known in America. On the left, pottery toy with wheels in Taxila (India), second century BC.  Taxila is situated 33º 44´N and 72º 49´E, 45km NW of Rawalpindi. On the right, dog or deer with painted muzzle and eyes. In Veracruz, Mexico (ca. 500 AD).

Stele with elephant in Ecuador. Stone slab with inscription written in Libyan, with an elephant in the upper part. Found in Ecuador, established as dating from 300 BC. Courtesy of Heinke Sudhoff, (Sorry Kolumbus).

Peruvian Quipu. Used during the Inca period to record accounts of various kinds. It was also used as a means of communication. Found in Ecuador, it dates from 300 BC. Courtesy of the International Red Cross office in Lima. From their January 1 2001 news magazine.

Main ocean currents. To provide a better understanding of transoceanic travel between Asia and America, we include a reproduction of the map showing ocean currents in the in the north and south Pacific. Courtesy of Albatros, Enciclopedia del mar, Barcelona 1974.

Map of Peru and location of Chinese placenames: From Cuenca del Pacífico: 4.000 años de contactos culturales.